The Spanish government has confirmed it will proceed with the sale of 400 laser-guided bombs to Saudi Arabia, days after saying the €9.2m (£8.2m) deal had been halted amid apparent concerns over the use of such weapons in the war in Yemen.

Josep Borrell, the foreign minister, announced the U-turn on Thursday, saying the government had reviewed the contract and felt it had to be honoured.

The decision came after protests by workers at the state-owned Navantia shipyard in southern Spain, who argued that abandoning the contract would lead the Saudi government to walk away from a €1.8bn deal to buy five warships.

“After an intense week’s work by various ministries, including the foreign ministry, the decision is that these bombs will be delivered to honour a contract from 2015, which was made by the previous government and in which no irregularity has been detected that would bar it from happening,” Borrell told Onda Cero radio.

The minister said the contract had been thoroughly reviewed by different ministries and checked three times by the interdepartmental commission that oversees arms sales.

Asked whether the Saudi government had suggested the purchase of the warships was dependent on the bomb deal, Borrell said: “Saudi Arabia looks at its arms deals as part of its overall relations.

“The ministry of defence and the foreign ministry have been talking about this and analysing it for a week. And I think we’ve come to the conclusion that this contract had to be honoured.”

Pressed on whether the Spanish government had received any guarantees that the bombs would not be used against civilians in Yemen, Borrell insisted they were precision weapons that “do not create collateral effects” and were accurate to a range of within a metre of their targets.

“That means that with this kind of weapon you don’t get the bombings that you get with less sophisticated weapons that are dropped rather randomly and which cause the kind of tragedy that we’ve all condemned,” he said.

Borrell said the announcement last week that the deal would be halted appeared to have arisen from confusion within the defence ministry.

“[It’s] been checking all the contracts and thought it had found something that needed looking at in this,” the minister said. “It wasn’t an arms sale by a business or manufacturer but part of our air force’s own stock. That must have stood out and meant the contract was looked at. But that’s all the information I have.”